转:1Z0-042记录(二)

81. You want to refer the employee personal information stored in operating system(OS) files in EMPLOYEE<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />

table. You plan to add a new column to EMPLOYEE table to achieve this.

Whichdatatype would you use for the new column?

A) BLOB

B) CLOB

C) BFILE

D) LONG RAW

Editor’s notes:oraclehas four big objects for lob type.it is blob，clob，nclob，bfile.

Blob Is used for storing image file.

Clob is used for storing large character data

Bfile is used for stroing external file for oracle.

Website associated:

http://www.itpub.net/viewthread.php?tid=995557&extra=&page=1

 

82. You want to monitor and control the resource usage by sessions. You want to be warned automatically

when more than 100 sessions are opened with your database. What action would you take to achieve this?

A) Use the Database Resource Manager.

B) Set the limits in the profiles used by users.

C) Modify the SESSIONS initialization parameter.

D) Set the warning threshold for theCurrent Logons Countmetric.

Editor’s notes:Current Logons Count is system metric values of oracle. You can see this value by querying v$sysmetric.

SELECT * from v$sysmetric t WHERE t.METRIC_NAME='Current Logons Count';

 

83. In your database, the STATISTICS_LEVEL initialization parameter is set to BASIC. What is the impact of this setting?

A) The optimizer statistics are collected automatically.

B) Only the timed operating system (OS) statistics and plan execution statistics are collected.

C) The Oracleserverdynamically generates the necessary statistics on tables as part of query optimization.

D) The snapshots for the Automatic Workload Repository (AWR) are not generated automatically.

E) Snapshots cannot be collected manually by using DBMS_WORKLOAD_REPOSITORY PACKAGE.

Editor’s notes:You can identify what have changed when you query the view(V$STATISTICS_LEVEL)

Answer B:plan execution statistics must be set when STATISTICS_LEVEL set ‘all’.

When the STATISTICS_LEVEL parameter is modified by ALTER SYSTEM, all advisories or statistics are dynamically turned on or off, depending on the new value of STATISTICS_LEVEL. When modified by ALTER SESSION, the following advisories or statistics are turned on or off in the local session only. Their system-wide state is not changed:

Timed statistics

Timed OS statistics

Plan execution statistics

 

88. Data files of which three tablespaces can be recovered by performing an open recovery? (Choose three.)

A) TEMP

B) UNDO

C) INDEX

D) SYSAUX

E) SYSTEM

Editor’s nots:temp tablespace does not need to recover.when you perform. open recovery, tablespace must be taken offline.So, except undo/system/temp tablespace ,all of other tablepsace can be recovered when database open.

 

95. Which two statements regarding archive log destinations are true? (Choose two.)

A) A maximum of 10 destinations can be specified.

B) The archive logs must be written to all the destinations.

C) The archive log files can be written only to local destinations.

D) The archiving information can be traced to the alert log file whenever the archiving to a destination is successful.

E) The number of archiving destinations must be equal to the number of archive processes

(ARCn).

Editor’s notes:The number of archiving processed must be relevant to the parameter value of LOG_ARCHIVE_MAX_PROCESSES.The default value of this parameter is 2.The actual number of archiver processes in use may vary subsequently based on archive workload. So,Answer E is worng.

 

103. Redo log files are not multiplexed in your database. Redo log blocks are corrupted in group 2, and

archiving has stopped. All the redo logs are filled and database activity is halted. Database writer has written

everything to disk. Which command would you execute to proceed further?

A) RECOVER LOGFILE BLOCK GROUP 2;

B) ALTER DATABASE DROP LOGFILE GROUP 2;

C) ALTER DATABASE CLEAR LOGFILE GROUP 2;

D) ALTER DATABASE RECOVER LOGFILE GROUP 2;

E) ALTER DATABASE CLEAR UNARCHIVED LOGFILE GROUP 2;

Editor’s notes:You can see the dedail description of this question in < Clearing a Redo Log File > of managing the redo log.

A redo log file might become corrupted while the database is open, and ultimately stop database activity because archiving cannot continue. In this situation the ALTER DATABASE CLEAR LOGFILE statement can be used to reinitialize the file without shutting down the database.

The following statement clears the log files in redo log group number 3:

ALTER DATABASE CLEAR LOGFILE GROUP 3;

This statement overcomes two situations where dropping redo logs is not possible:

·If there are only two log groups

·The corrupt redo log file belongs to the current group

If the corrupt redo log file has not been archived, use the UNARCHIVED keyword in the statement.

ALTER DATABASE CLEAR UNARCHIVED LOGFILE GROUP 3;

This statement clears the corrupted redo logs and avoids archiving them. The cleared redo logs are available for use even though they were not archived.

If you clear a log file that is needed for recovery of a backup, then you can no longer recover from that backup. The database writes a message in the alert log describing the backups from which you cannot recover.

Note:

If you clear an unarchived redo log file, you should make another backup of the database.

If you want to clear an unarchived redo log that is needed to bring an offline tablespace online, use the UNRECOVERABLE DATAFILE clause in the ALTER DATABASE CLEAR LOGFILE statement.

If you clear a redo log needed to bring an offline tablespace online, you will not be able to bring the tablespace online again. You will have to drop the tablespace or perform. an incomplete recovery. Note that tablespaces taken offline normal do not require recovery.

 

110. Which statement is true when you run theSQLTuning Advisor with limited scope?

A) Access path analysis is not performed for the SQL statements.

B) SQL structure analysis is not performed for the SQL statements.

C) SQL Profile recommendations are not generated for the SQL statements.

D) The staleness and absence of the statistics are not checked for the objects in the query supplied to the SQL Tuning Advisor.

Editor’s notes:You can see the detail explaination of sql tuning advisor inb12411- 12 Automatic SQL Tuning

SQL Tuning Advisor provides options to manage the scope and duration of a tuning task. The scope of a tuning task can be set to limited or comprehensive.

If the limited option is chosen, the SQL Tuning Advisor produces recommendations based on statistics checks, access path analysis, and SQL structure analysis. SQL Profile recommendations are not generated.

If the comprehensive option is selected, the SQL Tuning Advisor carries out all the analysis it performs under limited scope plus SQL Profiling. With the comprehensive option you can also specify a time limit for the tuning task, which by default is 30 minutes.

The example is :

dbms_sqltune.create_tuning_task (

 sql_text => l_sql,

  user_name => 'SYS',

 scope     => 'COMPREHENSIVE',

 time_limit => 120,

 task_name => 'TEST'

    );

 

113. You want to perform. a backup of your database to tape. Which backup format can you use?

A. backup set only

B.image copyonly

C. only user-managed backup

D. both image copy and backup set

E. only incremental image copy backup

Editor’s notes:image copy is just like os copy command. It copy thesingle datafile, archived redo log file, or control file.The difference of image copy and backup set shows fllowed:

1，在存储到磁盘上之前,backup set可以利用oracle自带的二进制压缩算法对数据文件和归档日志进行压缩，而image copy不行。

2，backup set不会包括空闲块，如果一个块从未被写入数据，则rman在进行的时候，会忽略这些空块，而image copy则不会，所以采用backup set通常比image copy要快而且占用空间更小。

3，增量备份可以通过backup set实现，不能通过image copy实现。

4，如果你为磁带安装了rman驱动的话，可以直接备份backup set到磁带，而image copy不能直接备份到磁带。

5，两者都可以通过rman转储，但backup set不能通过操作系统级别来生成和转储。

6，rman可以检测2者的是否损坏（corruption），通过操作系统工具进行image copy备份的时候，不能检查corruption.

proxy copy can be backuped into tape.But proxy copy can backup controlfile and spfile.

 

116. You specified extent management as local for a tablespace. How will it affect space management in the tablespace?

A) All the extents will be of the same size.

B) Bitmap will be used to record free and allocated extents.

C) Free extents will be managed by the data dictionary tables.

D) The tablespace will be system managed and the users cannot specify the extent size.

Editor’s notes:

Answer A:lmt makes the extents auto allocate.the minimum value is 8K,and the largest is 64K

Answer D:when you create tablesapce,you can configure the uniform. extent by using this statement:

CREATE TABLESPACE lmtbsb DATAFILE 'G:\ORACLE\PRODUCT\<?xml:namespace prefix = st1 ns = "urn:schemas-microsoft-com:office:smarttags" /><chsdate w:st="on" year="1899" month="12" day="30" islunardate="False" isrocdate="False">10.2.0</chsdate>\ORADATA\ORCL1\TEMP2.DBF' SIZE<chmetcnv w:st="on" unitname="m" sourcevalue="25" hasspace="False" negative="False" numbertype="1" tcsc="0">25M</chmetcnv>

   EXTENT MANAGEMENT LOCAL UNIFORM. SIZE 128K;

The above statement use lmt and assm.So, as you see, users can specify the extent size.

 

120. While planning to manage more than one database in your system, you perform. the following activities:

1. Organize different categories of files into independent subdirectories.

2. Use consistent naming convention for database files.

3. Separate administrative information pertaining to each database.

Which option corresponds to the type of activities performed by you?

A) Oracle Managed Files

B) Oracle Grid Architecture

C) Optimal Flexible Architecture

D) Oracle database architecture

Editor’s notes:The OFA standard is a set of configuration guidelines created to ensure fast, reliable Oracle databases that require little maintenance. This appendix contains the following sections:

OFA is designed to:

·Organize large amounts of complicated software and data on disk, to avoid device bottlenecks and poor performance

·Facilitate routine administrative tasks such as software and data backup, which are often vulnerable to data corruption

·Facilitate switching between multiple Oracle databases

·Adequately manage and administer database growth

·Help eliminate fragmentation of free space in the data dictionary, isolate other fragmentation, and minimize resource contention

Oracle Grid Architecture is used forrac

 

122. One of the redo log members in your database is lost. You queried V$logfile for further details. What would be the

member's status?

A. LOST

B. INVALID

C. EXPIRED

D. DELETED

E. CORRUPT

F. UNKNOWN

G. OBSOLETE

Editor’s notes:v$Logfile.status has four values.they are:

INVALID - File is inaccessible

STALE - File's contents are incomplete

DELETED - File is no longer used

null - File is in use

 

124.You want to set up the Oracle Database<chmetcnv w:st="on" unitname="g" sourcevalue="10" hasspace="False" negative="False" numbertype="1" tcsc="0"><a href="javascript.:;" target="_self" nclick="javascript.:tagshow(event, '10g');"><u><strong><font color="#000000"><a onclick="javascript:tagshow(event, '10g');" href="javascript:;" target="_self"><u><strong>10g</strong></u></a></font></strong></u></a></chmetcnv>installation to follow the French language, with<place w:st="on"><country-region w:st="on">France</country-region></place>as the territory, and the date to be displayed in French for all users' sessions. Which environmental variable would you set to achieve this objective?

A) NLS_LANG

B) NLS_LANGUAGE

C) NLS_TERRITORY

D) NLS_CHARACTERSET

E) NLS_DATE_LANGUAGE

F) NLS_LENGTH_SEMANTICS

G) NLS_NCHAR_CHARACTERSET

Editor’s notes:nls_lang is os parameter name.It consist of three different values:

NLS_LANG参数由以下部分组成:

NLS_LANG=<Language>_<Territory>.<Clients Characterset>

NLS_LANG各部分含义如下:

LANGUAGE指定:

-Oracle消息使用的语言

-日期中月份和日显示

TERRITORY指定

-货币和数字格式

-地区和计算星期及日期的习惯

CHARACTERSET:

-控制客户端应用程序使用的字符集

这三个部分可从nls_database_parameter视图中得到：

select * from nls_database_parameters where parameter in ('NLS_LANGUAGE', 'NLS_TERRITORY','NLS_CHARACTERSET');

web site associated:

http://junmail.**.com/blog/137996

http://topic.csdn.net/u/20090513/17/54cf483c-161e-4cfb-be5b-d0d779aa095e.html

http://www.blogjava.net/pengpenglin/archive/2008/04/23/195096.html

 

128. In the PROD database you have granted the RESUMABLE system privilege to the CONNECT role.

Resumable space operation has been enabled for all user sessions. You want users NOT to be aware of any

kind of space-related problems while performing transactions. Instead, you want the problem to be resolved

by a database trigger automatically. Which combination of triggering time and event would you use to achieve

this objective?

A) AFTER CREATE

B) AFTER SUSPEND

C) BEFORE CREATE

D) AFTER TRUNCATE

E) BEFORE SUSPEND

F) AFTER INSERT OR DELETE OR UPDATE

G) BEFORE INSERT OR DELETE OR UPDATE

Editor’s notes:There are four types of triggers.

Row Triggers and Statement Triggers

BEFORE and AFTER Triggers

INSTEAD OF Triggers ---used for views

Triggers on System Events and User Events

You can see the The detail description in <Oracle9i Database Concepts Part Number A96524-01>

This question is explain in this web site:

http://yangtingkun.itpub.net/post/468/14699

 

131. Which two statements are true regarding the SGA_TARGET initialization parameter? (Choose two.)

A) It can be increased up to the value of the SGA_MAX_SIZE parameter.

B) Increasing the value of SGA_TARGET up to the value of SGA_MAX_SIZE disables the automatic shared memory management feature.

C) Reducing the value of the SGA_TARGET parameter takes away memory from both autotuned and manually sized components.

D) Increasing the value of the SGA_TARGET parameter distributes the increased memory among all the autotuned components.

Editor’s notes:Dynamic Modification of SGA_TARGET

The SGA_TARGET parameter can be increased up to the value specified for the SGA_MAX_SIZE parameter, and it can also be reduced. If you reduce the value of SGA_TARGET, the system identifies one or more automatically tuned components for which to release memory. You can reduce SGA_TARGET until one or more automatically tuned components reach their minimum size. Oracle Database determines the minimum allowable value for SGA_TARGET taking into account several factors, including values set for the automatically sized components, manually sized components that use SGA_TARGET space, and number of CPUs.

The change in the amount of physical memory consumed when SGA_TARGET is modified depends on the operating system. On some UNIX platforms that do not support dynamic shared memory, the physical memory in use by the SGA is equal to the value of the SGA_MAX_SIZE parameter. On such platforms, there is no real benefit in setting SGA_TARGET to a value smaller than SGA_MAX_SIZE. Therefore, setting SGA_MAX_SIZE on those platforms is not recommended.

On other platforms, such as Solaris and Windows, the physical memory consumed by the SGA is equal to the value of SGA_TARGET.

When SGA_TARGET is resized, the only components affected are the automatically tuned components for which you have not set a minimum value in their corresponding initialization parameter. Any manually configured components remain unaffected.

 

145. In your Oracle<chmetcnv w:st="on" unitname="g" sourcevalue="10" hasspace="False" negative="False" numbertype="1" tcsc="0">10g</chmetcnv>database, you have scheduled a job to update the optimizer statistics at 05:00 pm

every Friday. The job has successfully completed. Which three pieces of information would you check to

confirm that the statistics have been collected? (Choose three.)

A) average row size

B) last analyzed date

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